Bicycles and other user-propelled vehicles are environmentally friendly methods of transportation. As concerns grow over pollution, traffic congestion, and other complaints commonly voiced about automobiles and other motorized modes of transportation, alternative forms of transportation which do not pollute or add to traffic congestion have become more and more popular. Such user-propelled vehicles are also an excellent form of exercise. They are typically excellent for aerobic and strengthening exercises.
Often it is desirable for a vehicle to be capable of carrying more than one person. This may be preferable when companionship is desired during exercise, for example, or when a child or disabled person is involved. One such vehicle is known commonly as a tandem bicycle. In this vehicle, one rider sits in front of another rider, with each having pedals for providing power, and the front user being provided with a handlebar to steer the vehicle. However, there are several drawbacks associated with tandem bicycles.
First, the drive assemblies on tandem bicycles are typically interconnected such that the pedals for each rider turn in unison. Therefore, both riders must typically pedal together, and neither rider can rest his or her feet on the pedals without them turning whenever the other rider is pedalling. Also, when one rider is in better physical condition than the other, that person will typically bear most of the load, and the other may not receive enough exercise.
Another problem associated with tandem bicycles is that only the forward rider is capable of steering the vehicle. In order for the other rider to be able to steer the vehicle, the riders would have to stop and exchange places. During long trips, it may be desirable to take turns at steering the vehicle. This cannot be performed without first stopping the vehicle and exchanging riders.
Another problem associated with tandem bicycles is that they must be balanced while riding. While all bicycles require a rider to remain balanced, a tandem bicycle complicates balancing because two independent riders must coordinate their movements in order to keep the vehicle balanced. It may be preferable in some instances to have a vehicle that is more stable and does not require riders to pay constant attention to their balance.
In order to provide better balance and stability, as well as provide separate drive assemblies, upright side-by-side bicycles have been constructed. These vehicles are often two standard upright bicycles which have been secured together side-by-side by a number of cross-braces interconnected therebetween, in order to provide a complete 4-wheeled vehicle. As these vehicles have four points of contact with the road, they are inherently better balanced, and less attention needs to be given to balancing by the riders. Also, as the two bicycles usually have independent drive assemblies, the pedals on each bicycle do not need to turn at precisely the same rate. Therefore, different amounts of power can be provided by each of the riders.
A number of drawbacks exist, however, in these upright side-by-side vehicles. First, while the balance and stability of these vehicles is much greater than a bicycle, the center of gravity for these vehicles is rather high since the riders sit upright. Therefore, greater stresses are placed on the cross-bracing and the vehicle may be prone to tipping over. Also, some of the upright side-by-side bicycles do not couple the steering systems for each of the independent bikes. Therefore, instead of only one rider being able to control the steering, both riders must pay attention to steering in order for the vehicle to operate safely. Some of the upright side-by-side bikes do use tie-rods or other coupling mechanisms in order to tie the handlebars together so that either rider can steer both bicycles when they are joined as a unit.
Another problem with upright side-by-side vehicles is that the connections between the bicycles are either permanent or very difficult to assemble and disassemble. Thus, when the two bikes are tied together, it is not easy to separate them so that each bike can be used independently. Another difficulty found with these upright side-by-side vehicles is that, once assembled, these vehicles are quite large and bulky, and take a significant amount of space to store.
Therefore, a need exists in the art for a vehicle capable of carrying two or more riders, which is stable and balanced, allowing for riders of different physical abilities, and allowing either rider to safely steer the vehicle. Further, there exists a need in the art for a side-by-side vehicle which is easy to assemble and disassemble, and which is easy to store.
There also exist in the art a number of different seating configurations in user-propelled vehicles which provide advantages over the typical upright position which is found in most bicycles. One such seating configuration is the recumbent seat. This configuration enables a rider to sit in a relaxed reclined position with support for the back, reducing lower neck and back strain, as well as general arm and leg fatigue. Such recumbent seating configurations are found in recumbent bicycles useful for one operator. Many of such recumbent bicycles, however, are difficult to steer, as the handlebars are typically placed underneath the seat, so that a rider has to reach under both sides of the seat in order to steer the vehicle. Other recumbent vehicles implement overhead handlebars which extend upward and outward from the fork, similar to many upright bicycles. These handlebars, however, can reduce visibility and interfere with the knees or legs of a rider, while being generally awkward to control. Therefore, a need also exists in the art for a recumbent bicycle configuration having a steering assembly which allows a rider greater control over steering the vehicle, while providing ample visibility and relatively unrestricted body movement.